1. Technical Field
The present invention relates to an image recording apparatus and an image recording method.
2. Related Art
An image recording apparatus has been described for recording text information or images on a recording medium by conveying a recording medium such as recording paper in a conveying direction, and recording on the recording medium by a method such as jetting ink droplets or applying impacts in dot units with a head that faces towards a recording face (see for example Japanese Patent Application Laid-Open (JP-A) No. 2007-22019). In this image recording apparatus a processing liquid is applied to the recording face of the recording medium to achieve higher quality images, and the recording head to recording medium distance is changed in order to prevent smudging occurring on the recording face due to contact or interference between the recording medium and the head(s).
There is also another image recording apparatus described in which means is provided for detecting signs of slackness in recording paper (continuous paper), increasing the throw distance between the head(s) and the recording paper when slackness of the paper is detected so as to prevent contact or interference between the recording paper and head(s) (see for example JP-A No. 2009-226839).
However, when there is a constant recording density with the head(s), unless the conveying speed for conveying the recording paper is also constant poor image quality with variation of the output image in the conveying direction results. In order to address this issue, in the image recording apparatus of JP-A No. 2009-226839, for example, a configuration is adopted in which the head(s) are lowered and moved to the recording position only after the recording paper conveying speed has achieved a recordable speed, and then recording is started. The head(s) are also lifted and moved to the standby position only after recording has been completed, and then recording paper conveying is stopped.
With a procedure such as described above there is no recording performed on the recording paper until the recording paper conveying speed has achieved a specific speed, namely while accelerating or decelerating. The recording paper conveyed during such intervals becomes “broke” and recording paper is wasted. Since broke increases according to both the acceleration duration and the recording speed, this leads to increased cost particularly for high speed recording.
However, were the head(s) to be moved to the recording position before accelerating the recording medium, since there is a possibility of the recording paper flapping during acceleration, consideration should be given to resulting problems such as contact or interference of the recording paper to the head(s), occurrences of poor imaging and damage to the heads.